drm/i915/pm: Print offending domain in refcount failure

If we experience a refcounting failure in a power domain/well (unref'ing at
least one too many times), log the name of the offending domain or well.

Signed-off-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448034934-11926-2-git-send-email-daniels@collabora.com

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index ec38409242d5..3fa43af94946 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -1499,11 +1499,15 @@ void intel_display_power_put(struct drm_i915_private *dev_priv,
 
         mutex_lock(&power_domains->lock);
 
-        WARN_ON(!power_domains->domain_use_count[domain]);
+        WARN(!power_domains->domain_use_count[domain],
+             "Use count on domain %s is already zero\n",
+             intel_display_power_domain_str(domain));
         power_domains->domain_use_count[domain]--;
 
         for_each_power_well_rev(i, power_well, BIT(domain), power_domains) {
-                WARN_ON(!power_well->count);
+                WARN(!power_well->count,
+                     "Use count on power well %s is already zero",
+                     power_well->name);
 
                 if (!--power_well->count)
                         intel_power_well_disable(dev_priv, power_well);